Electrical contact-clamp.



No; 740,358. PATENTED SEPT. 29, 1903.

P. J. ESMOND. I

ELECTRICAL GONTAGT CLAMP.

urmoumu 2mm mu m, 1902.

no menu.

mul 1/ WITNESSES: IN VENTOH Mm FJEamond- 1 UNIT D STATES iatented September 29, 1903.

PATENT OFFICE.

FREDERICK JOHN ESMOND, OF VANCOUVER, CANADA, ASSIGNOR OE ONE-THIRD TO FRED T. COPE AND CHARLES FREY, OF VANCOUVER,

CANADA.

ELECTRICAL CONTACT-SLAM P.

SPECIFICATION forming part of Letters Patent No. 740,358, dated September 29, 1903.

Application filed July 10,1902. Serial No. 114,984. (No model.) I

To a-ZZ whom it may concern:

Be it known that I, FREDERICK J onn Es- MOND, a citizen of the Dominion of Canada, residing at Vancouver, in the Province of British Columbia, Canada, have invented a new and useful Electrical Contact-Clamp, of which the following is a specification.

My invention relates to an improved electrical contact-clamp designed for wherever screw connections are at present used, but especially applicable to supersede such in cut-outs, branch boxes, or rosettes where it enables an efficient contact with the line-wires to be simply and expeditiously made.

The device is fullydescribed and illustrated in the following specification and drawings, in which-- Figure 1 is a side elevation of the clamp to an enlarged scale; Fig. 2, a plan of the same; Fig. 3, an end elevation in the direction of the arrow; Fig. 4-, a side elevation of a moditied form; Fig. 5, a section of a ceiling-rosette, showing the application of the clamp in a a. in Fig. l.

In the drawings,P indicates the insulatingbase to which the clamp is secured, and W the wire to be connected.

In the preferred form my device consistsof a base-plate 2, formed from a strip of sheet metal and having a depressed groove 2 extending longitudinally along the center of its width for about two-thirds of its length. 5 The strip is doubled back on itself, as at 3, and this portion forms the means by which the clamp as a whole is secured to the insulating-base by the screw 4, and to which the terminal screw 5 is connected in the usual manner. The strip is then bent upward for a short distance and then resumes the horizontal, as at 6, terminating in the hinge to which the clamping member 7 is connected by the hinge-pin 8. The clamping member 7 is constructed in one piece, the portion 7 which forms the hinge attachment, being die struck from the center of the body and bent over. One part of the clamp member projects outward toward the end and is bent 50 down toward the baseplate 2, being provided toward the end with a groove 7 to oppose the such; and Fig. 6, a cross-section on the line groove 2 of the base-plate. As this portion of the clamp member forms a lever by which the clamp is operated the extreme end is bent slightly upward to form an engagement for the finger-nail. On the opposite side of the hinge-pin the clamp member is bent down toward the base-plate in a cam or eccentric form, as 7, and is provided with an opposin g groove, as before, to engage the wire which it is. designed to clamp.

In application the clamp member is turned into the position indicated by dotted lines in Fig. 1, and the cleaned end of the wire it is desired to connect being placed in the groove 2 the clamp is brought down to the position as drawn, the end of 7 rubbing a good metallic contact in passing the center and the resilience of the portion 5, to which the clamp is hinged, enabling, the contact-bearings to adapt themselves to variation in the thickness of the wire.

Theopposing grooves of the base and clamp permit a very efiicient contact to be made, as the wire is partially encircled by the clamping members, and the device may be made conveniently small and of light material, as

the current will flow through both top and bottom members of' the clamp, to facilitate which it will be noticed that the clamp memher 7 beyond the width of the hinge portion is shaped to conform to the outside of the hinge portion of the part 5, which insures an ample contact at the hinge connection.

I do not confine myself to the particular manner of construction here illustrated,as such may be modified to suit the requirements of manufacture and varied conditions of application, and it mayfor some applications be found sufficient to simply clamp the wire against theinsulating-base without providing a conductive base-plate 2. The clamp will, under such conditions, be cheaper to manufacture; but I consider the addition of the base-plate an advantage, as the clamp is then self-contained and independent of the attachment to the insulator, while it has also a greater contact and conductive area.

Fig. 5 shows the application of my clamp to an ordinary ceiling-rosette, P being the insulating-base, p the bridge-piece of such, which separates the two connections, and C the cover, secured by the screws 5 and within which are the fuses and their attachments.

Having now particularly described my invention, I declare that What I claim as new,

and-desire to be protected in by Letters Patent of the United States, is

A contact-terminal of the class described comprising an insulating base member having groove inits upper face, and an aperture; a base-plate 2 fixedly secured to the insulating-base; a bolt 4: adapted to pass through the aperture in the base member for securing the base-plate 2 to the base member, said base-plate 2 having a portion bent backward upon itself as at 3, and a vertical and a horizontal portion 6, said horizontal portion 6 being disposed in a plane above the base-plate 2; a lever pivotally secured to the horizontal portion 6, said lever including a heel portion 7 forming a cam member and a lever portion 7 said lever portion 7 and said heel portion 7 each having a concave groove, said baseplate having a similar groove to coact with the concave groove, in the portion 7 and 7, said lever 7 and said base-plate 2 being normally held in engagement with each other and adapted to receive a contact-terminal in 

